Fixed Kewood toaster tripping rcd

My Problem

The several year old Kenwood TCM300 toaster started tripping the RCD (or RCCB or RCBO) due to a detected leaking current to earth.

My Fix

I inspected the heating elements with a torch (flashlight) and noted a build-up of toast crumbs at the bottom of the toast slot, such that the layer of adhering toast crumbs was bridging the gap between the heating wire and the metallic casing. Although subsequently I could detect no significant earth leak (resistance between live and earth pins >2Mohm), I very carefully removed this crumb layer with a 300mm long 3mm diamter pointed stick (bamboo skewer), being careful not to break the heating wires (plug disconnected of course). This cured the problem.

My Advice

Although the dry toast crumbs did not appear to be conductive, I assume in a damp kitchen or when toasting moist bread, the old toast crumbs absorb moisture and the salt in the old toast crumbs causes it to become electrically conductive.

This particular Kenwood toaster (TCM300) was particularly difficult to dismantle, so sometimes it worth trying a repair without dismantling which itself may cause dissassembly damage.